Matrix printer and interchangeable container for color ink supply

ABSTRACT

In an inkjet printer having at least one interchangeable container ( 16 ) for printing ink, having a holder ( 10 ) to hold the interchangeable container ( 16 ), having a switching device to block and enable the inkjet printer, having a signal transmitter ( 24 ) and a signal receiver ( 28 ) connected to the switching device, which are arranged on the holder ( 10 ), and having a signal transmitting device, on the interchangeable container ( 16 ), which transmits an enable signal from the signal transmitter ( 24 ) to the signal receiver ( 28 ) during or after the insertion of the interchangeable container ( 16 ) into the holder, the signal transmitting device is arranged in the interior of the interchangeable container ( 16 ) and has a signal input ( 38 ), a signal transmission element ( 40 ) and a signal output ( 48 ).

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is entitled to the benefit of and incorporates byreference essential subject matter disclosed in International PatentApplication No. PCT/DE99/02289 filed on Jul. 26, 1999 and German PatentApplication No. 19839225.7 filed on Aug. 28, 1998.

FIELD OF THE INVENTION

The invention relates to a matrix printer using interchangeable inkcontainer and having a means for preventing operation of the printerwith an improper ink container.

BACKGROUND OF THE INVENTION

A matrix printer of this type, designed as an inkjet printer, isdisclosed by the document EP 0 606 047 A2. Its print head has arelatively small supply volume for ink, which is connected via aflexible connecting line to an interchangeable container which containsa larger ink supply. The printing ink is led out of the interchangeablecontainer, through the connecting line, into the supply volume of theprint head. As a result, the inkjet printer can carry out print jobswith very high ink consumption without the printing operation beinginterrupted to refill the supply volume or to replace the print head.

Although the known inkjet printer starts a printing operation even whenno interchangeable container is connected to the supply volume in theprint head, in this case there is the risk that particularly long printjobs will be carried out only incompletely and/or erroneously and willtherefore have to be repeated.

U.S. Pat. No. 5,506,611 describes an inkjet printer and aninterchangeable ink container that can be operated therein. In order toverify the proper arrangement of the ink container inside a holderbelonging to the printer, inter alia a reporting system is proposedwhich is constructed as follows: provided on the printer is a shaft-likeholder, into whose clear space a projection projects. Provided on theupper side of the ink container is an opening which is closed by adisplaceable cover. When the ink container is inserted into the holder,the cover is held back by the projection, so that the opening in theupper side of the ink container is opened as the ink container isinserted further into the holder. This releases the pivoting path of aflag which, being driven by a spring, swings out of the ink containerand penetrates into a forked light barrier. The latter reports thepresence of an ink container in the printer to a printer control system.

A further drawback is that an interchangeable container with inkunsuitable for the operation of the inkjet printer can also be insertedinto the holder, and makes the print head unserviceable or damages itpermanently.

DE 91 16 990 U1 has therefore proposed to apply to the surface of an inkcontainer a pattern of lines which connects two contacts arranged on acontainer holder when the ink container is put correctly into thecontainer holder. The making of contact is reported to a control unit,which for its part enables the printing operation. In the case of thisarrangement, it is also disadvantageous that, by means of the improperconnection of the contacts, it is possible to feign a proper inkcontainer which, however, contains an ink which is unsuitable for theprinter. On the other hand, in the event of relatively long use of oneand the same ink container, oxidation of the pattern of lines and of thecontacts can occur.

U.S. Pat. No. 5,506,611 describes an inkjet printer and aninterchangeable ink container that can be operated therein. In order toverify the proper arrangement of the ink container inside a holderbelonging to the printer, inter alia a reporting system is proposedwhich is constructed as follows: provided on the printer is a shaft-likeholder, into whose clear space a projection projects. Provided on theupper side of the ink container is an opening which is closed by adisplaceable cover. When the ink container is inserted into the holder,the cover is held back by the projection, so that the opening in theupper side of the ink container is opened as the ink container isinserted further into the holder. This releases the pivoting path of aflag which, being driven by a spring, swings out of the ink containerand penetrates into a forked light barrier. The latter reports thepresence of an ink container in the printer to a printer control system.

It is the object of the invention to configure a matrix printer of thetype mentioned at the beginning, and an interchangeable container forprinting ink to be used with said printer, in such a way that theprinting operation can be enabled or blocked reliably if nointerchangeable container, or an unsuitable one, is inserted into theholder.

SUMMARY OF THE INVENTION

This object is achieved by a matrix printer having the features of claim1. Advantageous developments of the invention are specified in thedependent claims.

In order to block and enable the printing operation, the matrix printeraccording to the invention has a signal transmitter and a signalreceiver, which are formed on the holder, and also a signal transmittingdevice which is arranged on the interchangeable container. The receiptof an enable signal, emitted by the signal transmitter, by the signalreceiver is interrupted as long as the interchangeable container havingthe signal transmitting device is not inserted into the holder. Theprinting operation remains blocked and is enabled only when the signaltransmitting device of the interchangeable container, when the containeris inserted completely into the holder, passes on the enable signal tothe signal receiver.

The invention therefore firstly ensures that the printing operation isenabled only when an interchangeable container having theabove-described equipment is inserted into the holder. Secondly, aninterchangeable container without the signal transmitting device cannotbe operated with the matrix printer. In this way, the matrix printer istherefore simultaneously protected against the use of an interchangeablecontainer with unsuitable printing ink, which does not have the signaltransmitting device.

There is interaction between a signal input, a signal transmittingdevice and a signal output. The arrangement of signal input and signaloutput is made in such a way that the enable signal can be transmittedfrom the signal transmitter to the signal receiver on the holder. Thisarrangement makes the signal transmitting device particularly robustagainst external influences. In addition, the inkjet printer and theinterchangeable container, as a result of the precisely defined mutualarrangement of signal transmitter and signal input, on the one hand, andsignal output and signal receiver, on the other hand, and also acorresponding arrangement and configuration of the signal transmissionelement, bear additional features which protect against the use ofunsuitable interchangeable containers.

It is advantageous that the signal transmitting device in theinterchangeable container is mounted separately from the ink supply. Asa result, it is protected against possible damaging effects of theprinting ink, and otherwise necessary devices for sealing theinterchangeable container at the signal input and at the signal outputare dispensed with.

The use and transmission of a mechanical enable signal provides aparticularly simple and robust embodiment of the inkjet printer and ofthe interchangeable container. In this connection, a mechanical signalis understood to mean a symbol transmitted by the transport of movementenergy or potential energy in a system of coupled mechanical componentsand having a specific significance. The signal transmitter protrudesfrom a side of the holder that faces the interchangeable container,engages in the signal input of the interchangeable container when thelatter is inserted and comes into contact with a transmission elementwhich can be moved counter to spring force. During further insertion,the transmission element is forced by the signal transmitter and counterto the spring force to execute a movement by means of which it ispressed against the signal receiver, which is a switching element whichis connected to the switching device and is prestressed into an openedposition. When the interchangeable container has been insertedcompletely into the holder, the switching element is displaced by thetransmission element into a closed position, in which the printingoperation is enabled. In the case of this embodiment, therefore, it isnot possible to insert an interchangeable container with unsuitableprinting ink completely into the holder, which firstly protects theprinter and secondly indicates clearly to the operator of the printerthat he is trying to insert an interchangeable container with unsuitableprinting ink.

In particular, the signal transmitter can be designed as a pin and thetransmission element as a pivoting lever, whose axis of rotation runstransversely with respect to the insertion direction and on whose onearm the pin acts. As a result, the pin simultaneously fulfils the taskof a signal transmitter and that of a guide element as theinterchangeable container is inserted into the holder. Furthermore, adifferent type of matrix printer, which is serviceable only with aspecific different sort of printing ink, can be protected in aparticularly simple way against the use of unsuitable interchangeablecontainers by means of a slight alteration to the position of the pin onthe holder and a corresponding alteration in the arrangement of thesignal input and of the pivoting lever in the interchangeable containerduring the production of said printer.

The matrix printer can be both an inkjet printer and a dot matrixprinter. In the first case, the interchangeable container is designed asan ink container and, in the second case, as an ink ribbon cartridge.Both types of printer can be damaged by an unsuitable ink or ink ribbonimpregnation. The invention offers reliable protection for both.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following text, two exemplary embodiments of the invention willbe explained with reference to the drawing, in which:

FIG. 1 shows a longitudinally sectioned view of a part of a holder withan interchangeable container in its released position in accordance witha first exemplary embodiment of the invention,

FIG. 2 shows a longitudinally sectioned view of the part of the holderwith the interchangeable container in its inserted position inaccordance with the first exemplary embodiment of the invention,

FIG. 3 shows a longitudinally sectioned view of a part of a holder withan interchangeable container in its released position in accordance witha second exemplary embodiment of the invention, and

FIG. 4 shows a longitudinally sectioned view of the part of the holderwith the interchangeable container in its inserted position inaccordance with the second exemplary embodiment of the invention.

FIG. 5 shows an alternative embodiment of the invention in which theinterchangeable container is an ink ribbon cartridge.

DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 shows a holder 10 for use in an inkjet printer according to afirst exemplary embodiment of the invention. As viewed in longitudinalsection, the holder 10 has a rectangular frame 12 having a first opening14 on its upper side, which is used for the insertion and withdrawal ofan interchangeable container 16. During the insertion operation, theinter changeable container 16 is firstly put loosely from above, throughthe opening 14, into a compartment 18 which is arranged inside the frame12 and can be displaced in the latter in an insertion direction 20.

A side wall 22 of the frame 12, arranged on the left in the illustrationof FIG. 1, has on its inner surface, which points in the directionopposite to the insertion direction 20, a pin 24 which, at approximatelya right angle to the inner surface, protrudes from the latter in thedirection of the compartment 18. Likewise formed on the left-hand sidewall 22, underneath the pin 24, is an opening 26. It accommodates anelectrical switch 28 having a signal receiver in the form of a switchingpin 30 which is prestressed elastically into an opened position of theswitch 28 and can be moved in the direction 20 counter to a springforce, and which is approximately the same length as the pin 24.

Formed on a left-hand side wall 32 of the moveable compartment 18 and aleft-hand side wall 36 of the interchangeable container 16 are,respectively, an upper opening 34 and 38. The upper openings 34 and 38,as viewed in cross section, have a shape that corresponds to thecross-sectional shape of the pin 24 and are aligned with the latter whenthe interchangeable container is inserted into the compartment 18.

In the interior of the interchangeable container 16, a transmittingdevice in the form of a two-arm pivoting lever 40 is mounted such thatit can be rotated about its axis of rotation 42, its upper and lowerarms 40 a and 40 b protruding to an approximately equal length from theaxis of rotation 42. The axis of rotation 42 runs horizontally and, atthe same time, transversely with respect to the insertion direction 20,and is mounted on the interchangeable container 16 close to the sidewall 36 and, as viewed in a vertical direction, approximately centrally.

A compression spring 44 is fixed at one end to the lower arm 40 b of thepivoting lever and at the other end to the left-hand side wall 36 of theinterchangeable container 16. As a result, the pivoting lever 40 isprestressed into a position in which the upper arm 40 a rests with itsupper end on the left-hand side wall 36 of the interchangeable container16, above the opening 38. An opening 46 and 48, respectively, is in eachcase formed on the left-hand side wall 36 of the interchangeablecontainer 16 and the left-hand side wall of the compartment 18, which isadjacent in the insertion direction 20, opposite the lower end of thelower arm 40 b of the pivoting lever 40.

If the compartment 18 is moved in the insertion direction 20, the pin 24moves into the interchangeable container 16 through the openings 34 and38, and the switching pin 30 moves into the interchangeable container 16through the openings 46 and 48, approximately simultaneously. In theprocess, the pin 24 encounters the upper arm 40 a of the pivoting lever40 and deflects the latter counter to the force of the compressionspring 44. At the same time, its lower arm 40 b is pivoted in thedirection of the side wall 36 of the interchangeable container, whichmoves the switching pin 30 of the switch 28 as soon as the compartment18 is resting on the inner surface of the side wall 22 of the frame 12(FIG. 2). With this movement of the switching pin 30 of the switch 28,an electrical circuit (not illustrated) is closed, and controls theenabling of the inkjet printer for printing operations. Only when thecircuit is closed will the inkjet printer be enabled. The maximumpossible operating travel of the switching pin 30 is defined in such away that it must in any case pass through the openings 46, 48 before theleft-hand side wall 32 of the compartment 18 is resting on the frame 12.

It is also possible to put the interchangeable container 16 directlyinto the frame 12. The compartment 18 and, with the latter, the openings34 and 48 can then be omitted.

FIG. 3 shows a holder 50 for use in an inkjet printer according to asecond exemplary embodiment of the invention. As viewed in longitudinalsection, the holder 50 has a rectangular frame 52 with an insertionopening 54 on its upper side for the insertion and withdrawal of aninterchangeable container 56. During the insertion operation, theinterchangeable container 56 is firstly put loosely from above into acompartment 58 which is arranged inside the frame 52 and can bedisplaced in the latter in a horizontal insertion direction 60.

Arranged at the end of the frame 52 which is on the left in theillustration of FIG. 3 is a closing lever 62, which is mounted such thatit can be rotated about an axis of rotation 64 fixed to the frame. Theclosing lever 62 may be part of a closure cap (not illustrated further)for the insertion opening 54. The 35 axis of rotation 64 of the closinglever 62 runs horizontally and, at the same time, transversely withrespect to the insertion direction 60. FIG. 3 shows the closing lever 62in an opened position, in which it extends upward vertically. As viewedfrom above, it has a rectangular profile with a long side 67 extendingtransversely with respect to the insertion direction, and a largelyrectangular transverse side 68 which faces the observer and broadensonly at its lower end in the shape of a curve 70 which encloses the axisof rotation 64, the curved edge pointing in the direction opposite theinsertion direction 60.

Formed in this broadened portion of the transverse side 68 is a guideslot 72, which extends essentially parallel to the curved edge 70. Theguide slot 72 has an end close to the axis of rotation and an end remotefrom the axis of rotation. The guide slot 72 approaches the axis ofrotation 64 continuously in a portion 72′, starting from its end remotefrom the axis of rotation 64, and at a point corresponding to a pivotingangle α of the closing lever 62, merges into a second portion 72″ whichextends circularly around the axis of rotation 64. In the openedposition of the closing lever 62 illustrated in FIG. 3, the near end ofthe guide slot 72 is located above the axis of rotation 64 and at thesame height as the latter, as viewed in the insertion direction 60. Theend of the guide slot 72 which is remote from the axis of rotation 64is, by contrast, located to the right of the axis of rotation 64 and isat the same vertical height as the latter. A guide pin 74 engages in theguide slot 72, at that end of the guide slot 72 which is remote from theaxis of rotation 64 when the closing lever 62 is in the opened position.The guide pin 74 is formed on that side surface of the compartment 58which faces the observer but is not illustrated in FIG. 3.

The guide pin 74 can alternatively also be arranged on theinterchangeable container 56. In this case, the guide slot 72 is open atits end remote from the axis of rotation 64, so that it can bedisengaged from the guide pin 74 for the insertion and removal of theinterchangeable container 56 into and from the compartment 58. This isparticularly advantageous when—according to an alternative embodiment ofthe holder 50—the compartment 58 is dispensed with and theinterchangeable container 56 is put directly into the frame 52.

On the inner surface of its long side 67 which points to the right inthe illustration of FIG. 3, the closing lever 62 has a signaltransmitter in the form of a pin 76, which protrudes approximatelyvertically from said pin. Its vertical position on the closing lever 62is determined by the fact that, in the event of a pivoting movement ofthe closing lever 62 in the direction 66, it moves into an opening 78arranged on the upper side of the interchangeable container 56. Thiswill be discussed in more detail below.

Mounted in the interchangeable container 56 such that it can be moved inthe axial direction is a transmitting device in the form of a pin 80which has a vertical longitudinal axis whose imaginary extension runsapproximately through the center of the opening 78. For this purpose, aweb 82 having an opening enclosing the cross section of the pin 80 isfixed to an inner wall of the interchangeable container 56. The pin 80is held, with the aid of a helical compression spring, which is fastenedat its upper end to said pin and at its lower end rests on the undersideof the container 56, in a position in which its upper end is arrangedapproximately underneath the opening 78 and its lower end is arrangedapproximately above an opening 86 in the underside of theinterchangeable container 56, said opening being arranged in extensionof the pin.

An opening 88 on the underside of the compartment 58 is aligned with anopening 94 in the bottom of the frame 52 when the compartment 58 islocated in the position shown in FIG. 4. A signal receiver in the shapeof a switching pin 90 and belonging to a switch 92 arranged underneaththe frame 52 and projects into the opening 94, without projecting intothe interior of the frame 52. In terms of construction and functioning,the switch 92 corresponds to the switch 28 described with reference tothe first exemplary embodiment.

In order to insert the interchangeable container 56 put loosely into theframe 52, the closing lever 62 is pivoted in the direction 66. In theprocess, as is known from slotted guides of this or similar type, theguide pin 74 is used to exert a force, acting in the insertion direction60, on the compartment 58 or the interchangeable container 56, so thatthe interchangeable container 56 and the compartment 58 are movedtogether in the insertion direction 60. After the pivoting lever 62 hasbeen pivoted through the angle α the interchangeable container 56 islocated in its working position shown in FIG. 4. If the pivoting lever62 is pivoted further in the direction of the arrow 66, the pin 76arranged on the pivoting lever 62 engages in the opening 78 on the upperside of the interchangeable container 56, comes into contact with theupper end of the pin 80 in the interchangeable container 56 duringfurther movement of the pivoting lever 62, and presses said pin, counterto the spring force, downward and successively into the opening 86, theopening 88 located in the compartment 58 and against the switching pin90 of the switch 92. In the position which is illustrated in FIG. 4 andin which the interchangeable container 56 has been inserted completelyinto the holder 50, and the pivoting lever 62 is located parallel to theupper side of said container, the pin 80 operates the switch 92 and inthis way completes an electrical circuit explained with reference to thefirst exemplary embodiment, by which means the inkjet printer is enabledto print.

The side wall 96 of the frame 52 which is on the left in FIGS. 3 and 4has a further switch 98 inserted into it in such a way that itsswitching pin 100 projects into the interior of the frame 52. In theposition illustrated in FIG. 4, the further switch 98 is operated by theleft-hand side wall of the compartment 58 or, if the latter is omitted,by the left-hand side wall of the interchangeable container 56.

By means of a logical combination of the switching states of theswitches 92 and 98, a security concept is implemented as follows: if aninterchangeable container 56 is to be put into the compartment 58, theswitches 92 and 98 must be unoperated. After the interchangeablecontainer 56 has been put in and the closing lever 62 has been pivotedinto the closed position, the switch 92 is operated first, and thefurther switch 98 is operated only later. Only in the case of thischronological sequence of the switching edges will the printer beenabled. This therefore prevents a manipulation to the effect that oneof the switches 92, 98 is blocked in its operated position, and in thisway a proper interchangeable container is feigned.

The above-described security concept can also be used in the case of theholder 10 in the first exemplary embodiment, as illustrated in FIGS. 1and 2. It is a precondition that a further switching element,corresponding to the further switching element 98 in terms ofarrangement and function, is provided.

As mentioned, the matrix printer with which an interchangeable inkcartridge of this invention instead of being an inkjet printer can alsobe a dot matrix printer wherein the ink is provided by way of an inkribbon cartridge. Such an embodiment of the invention is shown in FIG. 5wherein an ink ribbon container or cartridge 16′ having an ink ribbon106 and an ink ribbon reservoir 104 is held in use by a holder 10′, withthe cartridge 16′ being moved in the direction 20′ to bring it into theposition at which it is held in use by the holder 10′. The illustratedparts of FIG. 5 called out by primed referenced numbers correspondrespectively to the parts of FIGS. 1 and 2 called out by the sameunprimed reference numbers, so the signalling functions performed as theink ribbon cartridge 16′ are moved onto the holder 10′is the same asthose performed when the interchangeable container 16 of FIGS. 1 and 2is moved onto the holder 10.

What is claimed is:
 1. A matrix printer having a moveable print head, atleast one interchangeable ink container for a printing-ink supply andhaving an interior space free of printing ink, and a holder to hold theinterchangeable container, a means for preventing operation of theprinter with an improper ink container, said means comprising: a firstswitch to block and enable the printing operation, a mechanical signaltransmitter and a mechanical signal receiver arranged on the holder, anda mechanical signal transmitting device arranged in the interior spaceof the interchangeable container for transmitting a mechanical inputsignal from the mechanical signal transmitter to the mechanical signalreceiver during or upon an insertion of the interchangeable containerinto the holder, the signal transmitter during the insertion of theinterchangeable container being moveable into the interior space of theinterchangeable container through an opening in a wall of theinterchangeable container, said signal receiver being associated withsaid switch so that an input signal from the signal transmitter istransmitted to the signal receiver by the signal transmitting device andis converted to an output signal applied to the signal receiver andthrough the signal receiver to the switch.
 2. The combination defined inclaim 1, wherein: the signal transmitter is a pin on a side of theholder which faces a surface of the interchangeable ink container whichpoints in an insertion direction of the container, the signaltransmitting device is a two-armed pivoting lever with an axis ofrotation running transversely with respect to the insertion directionand on one arm of which lever the pin acts, said signal receiver is aswitching pin of the switch arranged on the same side of the holder asthe pin and operated by a second arm of the pivoting lever, said switchbeing pre-stressed to an unoperated condition.
 3. The combinationclaimed in claim 2, wherein: the switching pin projects through a wallof the holder and, when an interchangeable ink container is moved into aworking position, penetrates into the interior space of theinterchangeable ink container through an opening in the surface pointingin the insertion direction.
 4. The combination claimed in claim 1,wherein: on the holder there is provided a compartment to hold theinterchangeable container, said compartment being movable between aholding position and a locked position, in which locked position amechanical signal is transmitted from said signal transmitter to saidswitch.
 5. The combination claimed in claim 1, wherein: the printer isan inkjet printer, and the interchangeable container is designed to holdprinting ink.
 6. The combination claimed in claim 1, wherein: theprinter is a dot matrix printer, and the interchangeable container isdesigned as an ink ribbon cartridge.
 7. The combination claimed in claim1, wherein: on the holder there is provided a pivoting closing lever forlocking the interchangeable container in the holder and having a signaltransmitter in the form of a pin for operating the signal transmittingdevice, with said signal transmitter pin being so arranged on the leverthat in a closed position of the closing lever, the signal transmitterpin, the signal transmitting device, and the signal receiver arearranged along a straight line of action, so that movement of saidsignal transmitting device is transmitted along said straight line ofaction from said signal transmitter pin, through the signal transmittingdevice, to the signal receiver.
 8. The combination claimed in claim 7,wherein: an opening is let into the bottom of the holder, and the signalreceiver is a switching pin of the switch, which switching pin isaligned with the opening and which switch is located underneath thebottom of the holder.
 9. The combination claimed in claim 1, wherein: asecond switch is incorporated in a side wall of the holder which secondswitch limits the insertion movement of the interchangeable containerand has a switching pin which projects into the interior of the holderand is moved with the interchangeable container as the interchangeablecontainer is moved in the insertion direction as the container isinserted into the holder.
 10. The combination claimed in claim 9,wherein: before an interchangeable container is put into the holder bothof said first and second switches are unoperated, during the insertionmovement, the first switch and then the second switch are operated, andthe printer is enabled only after this chronological sequence of switchoperations occurs.
 11. An interchangeable container for a printing-inksupply for a matrix printer having a mechanical signal transmitter and aswitch that can be operated to control the enabling of printing, theinterchangeable container comprising: a body with a wall having anopening for receiving the signal transmitter of the printer, as an inputsignal, when the interchangeable container is inserted into the printer,and a mechanical signal transmission element carried by said body andoperable by said transmitter when the interchangeable container isinserted into the printer for transmitting said input signal to saidswitch as an output signal from the interchangeable container whichoutput signal operates the switch to enable printing by the printer. 12.The interchangeable container claimed in claim 11, wherein: the signaltransmission element is provided inside the interchangeable containerbody, and the input signal and the output signal appear at a common wallof the interchangeable container.
 13. The interchangeable containerclaimed in claim 11, wherein: said interchangeable container is an inksupply container for an inkjet printer.
 14. The interchangeablecontainer claimed in claim 11, wherein: said interchangeable containeris an ink ribbon cartridge.